The prior art includes a disclosure that an object beam and a reference beam are separated to different optical paths and then the optical paths are joined again together to take the object beam at a periphery of a light beam and the reference beam at a center of the light beam, so that the object beam and the reference beam can be focused as circular polarizations different in rotating direction from each other concentrically on a recording medium, thereby causing interference between the two light beams in a thin-film polarization hologram record carrier (see WO 02/05270 A1).
Furthermore, there is known an art that a signal-beam optical system including a spatial light modulator is arranged opposite, sandwiching a recording medium, to a reference-beam optical system for exiting the reference beam so that reference and signal beams can be irradiated to an information record layer concentrically and at the same position in the surfaces opposite to each other while converging those to the minimal in diameter, thereby volumetrically recording a hologram in the recording medium (see Japanese Patent Laid-Open No. 2002-123948).